What's the Name of That Book??? discussion

I read that book in late 90's or early 2000's.

The story followed colony ship (one of many) from Earth. The ship was intelligent and cycling around the colonies it once helped establish, observing their development, and - from time to time - offering individuals a ride from one colony to another.

Book basically was made out of storied about those individuals and their reaction when watching or trying to integrate with new environments.

I remember there was one colony where people mutated into blobs, another one where they got ferral because of some mushroom spores and one where people lived in nebula around dead star, devoid of biomatter and they had to recycle anyone who could not work.